Ocean bottom seismometer data off the Nicoya and Osa peninsulas of Costa Rica, acquired during R/V Maurice Ewing expedition EW9502 (1995)

TICOSECT (Trans Isthmus Costa Rica Scientific Exploration of a Crustal Transect), a joint German, Costa Rican and UTIG program, collected seismic refraction data and two-channel reflection data. The objective was to investigate the upper plate response to subducting plate morphology and seamounts as subduction zone asperities. The project was a combined onshore-offshore refraction experiment along three transects (Experiments 1, 2 and 3) and an intense 3-D OBS focus in on the shelf just southeast of the Nicoya Peninsula as part of Experiment 2. Experiment 1 across central Nicoya consisted of dip lines 101 and 102 and strike lines 103, 104 and 105. Twenty OBSs or OBHs were deployed here. Onshore a 3.6 km cable was deployed and 30 PDAS-100 seismographs extended up to 140 km from the coast. Experiment 2 just southeast of the Nicoya Peninsula consists of 37 dip lines, 301-237, and 5 strike lines, 238-242. Thirty OBSs or OBHs were deployed with a separation of 5 km by 1 km and 3 additional OBSs were deployed on extended lines. Experiment 3 was just northwest of the Osa Peninsula consisting of dip lines 301 and 302, and two strike lines, 303 and 304. A total of 26 instruments were deployed on this experiment.